1. Technical Field
This invention generally relates to screen printing apparatus, commonly known as silk screening printers, and more particularly, this invention relates to a multiple screen printing device for the printing of numbers on sports jerseys and the like or multicolor or several multicolor designs for long term periodic use.
2. Background Art
One of the more common and most versatile of the printing processes is that of screen printing, or more commonly known as silk screen printing. Screen printing can be used to print on paper products, wood, plastics, textiles, etc. The instant invention is concerned with industrial use of screen printing for the printing of designs on textiles used in clothing, home decorating and the like. Because of the extreme versatility associated with the screen printing process, screen printing is the method of choice for a wide variety of mediums. Also, the screen printing process is well suited for printing designs on textile articles after they have been assembled, e.g., shirts, uniforms, hats and the like. This is the primary concern of the instant invention. Particularly, the instant invention is concerned with the printing of numbers and multicolor designs on sports jerseys, etc.
Printing numbers on sports jerseys, pants and the like is somewhat of a specialized process since it is relatively labor intensive. This is because a separate screen is required for each digit of the number. For complicated numeral designs which require multiple screens for each digit, such as multiple colors, borders, etc., the process can be too costly to be profitable due to the shear number of screens and the labor involved. One can easily calculate the amount of time necessary to print a different two digit number on each of thirty or more jerseys.
To accommodate printing applications which require multiple screens, prior artisans developed the rotary printing press which has a plurality of printing screens, typically four or six, secured to a rotating carriage. The desired screen is rotated into position above the printing platen and the jersey is manually aligned on the platen to insure proper registration of each digit. FUCHS, U.S. Pat. No. 4,084,504, teaches one such rotary press which incorporates an unusually large number of printing screens secured to a plurality of rotary carriages and further incorporates multiple printing platens to accomplish number printing. The apparatus is necessarily large and complex.
HARPOLD, U.S. Pat. No. 4,809,604, takes the rotary printing concept one step further by adding an adjustable, movable platen assembly which includes a sophisticated registration system for use with large screens having a multiplicity of numbers thereon. The printing platen is angular in shape to provide dual printing surfaces and is mounted on a reciprocating carriage for positioning under any one of a plurality of masks, arranged linearly on a printing screen. To be effective, the apparatus needs to use oversize screens in order to hold the multiplicity of designs or masks.
Obviously these machines, as well as all the other numeral printing setups of which the inventor is aware, are quite large, complex and expensive.
What is needed is compact, efficient and relatively inexpensive numeral screen printing apparatus which uses standard sized screens and yet provides sufficient flexibility to accommodate complex printing jobs. It is therefor an object of the present invention to fulfill these needs. It is a further object of the present invention to provide a relatively simple screen printing press for the printing of multiple digit numerals which is durable and easily maintained.